From Fort Worden’s press release: “To compose the “Atlas Eclipticalis,” John Cage used the Atlas Eclipticalis, an atlas of the stars published in 1958 by Czech astronomer Antonín Becvár, superimposing musical staves over the star charts in this atlas. The brightness of the stars was translated into the size of the notes in the composition. The work, commissioned in 1961 by the Montreal Festivals Society, was completed in 1962 and comprises 86 instrumental parts (for full orchestra) “to be played in whole or part, any duration, in any ensemble, chamber or orchestral.”